subroutine methane_init()
use molecule
implicit none
   !-------------------------------------------------------------------------
   real(q), parameter :: r23 = sqrt(2.D0/3.D0), r2_3 = sqrt(2.D0)/3.D0, r3 = 1.D0/3.D0
   real(q), parameter :: bl = 1.1D0
   !-------------------------------------------------------------------------
   natom    = 5
   neighmax = 4
   molname  = "methane"
   !
   if ( allocated(neigh   )) deallocate( neigh )
   if ( allocated(element )) deallocate( element )
   if ( allocated(molpos  )) deallocate( molpos  )
   allocate( element(natom), neigh(neighmax, natom), molpos(3,natom), chg(natom) )
   !
   element( 1) = "CT"
   element( 2) = "HT"
   element( 3) = "HT"
   element( 4) = "HT"
   element( 5) = "HT"
   !
   neigh(:, 1) = (/ 2, 3, 4, 5 /)
   neigh(:, 2) = (/ 1, 0, 0, 0 /)
   neigh(:, 3) = (/ 1, 0, 0, 0 /)
   neigh(:, 4) = (/ 1, 0, 0, 0 /)
   neigh(:, 5) = (/ 1, 0, 0, 0 /)
   !
   molpos(:,1) = (/ 0.D0, 0.D0, 0.D0 /)
   molpos(:,2) = (/ 0.D0, 0.D0,-1.D0 /)
   molpos(:,3) = (/ 0.D0, (r2_3+r2_3), r3 /)
   molpos(:,4) = (/ -r23, -r2_3, r3 /)
   molpos(:,5) = (/  r23, -r2_3, r3 /)
   chg         = (/ -0.24D0, 0.06D0, 0.06D0, 0.06D0 /)
   !
   molpos = molpos * bl
   !-------------------------------------------------------------------------
end subroutine methane_init
